Research On Obstacle Avoidance Planning Of Hydraulic Quadruped Robot Based On ROS

With the continuous development of science and technology in recent years,robot technology has become the focus of people all over the world.The research of bionic robots has become a hot spot for scholars in different fields.Hydraulic quadruped robots have outstanding performance in bearing capacity and adaptability to changing environment.In terms of motion,gait planning has an important influence on the stable motion of hydraulic quadruped robot.In this paper,the accuracy of motion control and obstacle avoidance motion planning of hydraulic quadruped robot are studied.Firstly,the kinematics characteristics of hydraulic quadruped robot are studied and its structure is analyzed.The structure is simplified by D-H method and its kinematics model is established.The forward kinematics and reverse kinematics of the quadruped robot are solved and the relative relationship between the foot coordinates and the joint is analyzed.In order to understand the motion principle of the robot more fully,the single leg motion control of the robot is experimented on the physical prototype test-bed of the hydraulic quadruped robot.The parameters and curves of the single leg motion are obtained through the experiment as the basic data for simulation.Based on the theory and practice,the robot is simulated.In this paper,virtual simulation is used to control single leg,and a series of popular robotic simulation platforms are listed to illustrate these platforms.In order to meet the requirements of robot simulation,the same simulation platform is proposed for robot control and motion planning.Taking into account factors such as data transmission speed and compatibility issues,the ROS(Robot Operation System)platform was finally selected.The ROS simulation platform is built and the robot model is imported into ROS to obtain URDF(Unified Robot Description Format)file,and the robot model is displayed by visual tool Rviz(ROS Visualization).Combining with the experimental data,the kinematics analysis of URDF file is carried out by using MoveIt! Toolkit,and the relevant documents for its callable and motion planning are configured to simulate the motion of the robot's single leg.Aiming at the single-leg obstacle avoidance motion planning problem of hydraulic quadruped robot,the RRT(Rapidly-exploring Random Trees)algorithm and RRT_Connect algorithm are analyzed,and a more suitable algorithm is selected to solve it,and the optimal path is obtained.It lays a foundation for the follow-up study of obstacle avoidance.